The present invention relates generally to printing apparatus or composing systems and more particularly to an improved printing apparatus or composing system of the type involving the use of a pressure process to transfer dry film impressions onto an image carrying tape. Such apparatus or system includes a printing station, a printing force generating means, a tape and associated carbon ribbon, a type disc or font element with raised characters positionable in printing alignment with the printing stations, and means for advancing the tape and ribbon with respect to the printing station. This type of apparatus or composing system has particular application in the printing of relatively large characters for use in preparing lettering for engineering drawings, flip charts, overhead transparencies, posters, newspaper headlines, advertising brochures and the like. These characters are generally larger than characters produced by most typewriters or other more conventional means.
In dry lettering printing processes a high pressure is utilized to transfer dry carbon or other ink or color material from a ribbon onto an image carrying tape. A type disc or font element having raised surfaces corresponding to the particular image desired to be printed is commonly used in such a process. Successful prior art machines and apparatus used by those employing dry lettering processes are shown and described in U.S. Pat. Nos. 3,834,507; 3,912,064; 4,015,700; 4,108,556 and in U.S. Pat. No. 4,243,333 issued Jan. 6, 1981. While each of these prior art machines has been capable of accurately generating high quality printing and lettering results, there is a need for a higher speed printing apparatus which maintains consistency in accuracy, quality and positioning, thus enabling users to produce display quality headlining in-house at a much higher rate than can be produced manually, thereby reducing the need for a large number of such printing machines or systems and, for repetitive printing, to enable the user to convey the information desired to be printed and the number of copies to be printed and obtain from that information the desired numbers of copies each of which is produced with the same high degree of accuracy and quality.
In an apparatus or system of the type described the operator manually moved the font to the character or symbol desired and pressed the print button. Thereafter the character position was precisely aligned by an electromechanical mechanism and a printing pressure was generated to print the character, after which the tape was advanced. While high quality printing was obtained in this manner, the tape could be printed no faster than the manual movement of the operator and accuracy was dependent on the dexterity and attention of the operator. If the operator were less skilled or the operator's attention lagged, accuracy could be affected requiring the manual printing of entirely new tapes.